It's widely known that the OS X Services infrastructure was completely overhauled (and made significantly more useful) in Snow Leopard. What virtually no one seems to be aware of is that Apple released a 'Services Manager' tool as long ago as 2009, which offers significant advantages over using the built-in support in the Keyboard preference panel.

In Snow Leopard (and now in Lion), it's possible to create your own Services (using e.g. Automator), and it's also possible to disable or enable Services provided either by applications or the system itself, by going to the Keyboard Shortcuts tab of the Keyboard preference panel.

However, the Keyboard preference panel has a number of limitations when it comes to editing Services, and unfortunately these limitations add up to it being just about unusable in practice. For example, while you can activate or deactivate a particular Service, there's no way to specify whether that Service will only be available on the Services menu, or (much more usefully) on relevant contextual menus as well. OS X seems to decide which Services appear on contextual menus based on its own arcane rules.

Services are listed by name only in categories based on their function. There's no easy way to see whether a particular Service is offered by the system itself, a third party application, or (say) an Automator workflow in /Library/Services or ~/Library/Services.

Back in pre-10.6 days, when there was no officially supported way of editing Services, a free tool called Service Scrubber by Many Tricks Software could be used for this purpose. Due to the changes made to Services in Snow Leopard, Service Scrubber no longer works in 10.6+. I've often wished there were a modern replacement.

As it turns out, there is! A tool named Service Manager is provided by Apple itself, hidden away on its macosxautomation.com website. You can download it here, and you'll find it provides all the functionality mentioned above, and more. Services Manager was intended for use with Snow Leopard, but I have so far found no problems using it in Lion.

[crarko adds: Works the same in either Lion or Snow Leopard. This is a great little utility.

Note: since some people seem to be freaking out in the comments here is some referential information about Sal. He's pretty much the boss of Services.]

I can't tell if the app is actually official (apart from license agreements, which can easily be faked by copy and pasting). There's no "(c) Apple" in the app menu -> About Service Manager, which is perhaps the killer blow indicating this isn't an official app. Apple always make that kind of thing very, very clear.

This tip needs editing to point all of this out, and that this is essentially a third-party app masquerading as an official app.

Sal Soghoian is a long time AppleScript advocate who is now a product manager in the automation group at Apple, which is responsible for AppleScript, Automator, and Terminal in OS X. He routinely gives talks about the automation features in OS X, on behalf of Apple.

That said, the web site is his, not Apple's, and the software on that site would be provided by him, not Apple. But that is perfectly clear if you visit the website. So it's "3rd party" software written an Apple employee.

You won't find a more reliable source if you're looking for OS X automation information and tools.

IMPORTANT: This Apple software is supplied to you by Apple Computer, Inc. (“Apple”) in consideration of your agreement to the following terms, and your use, installation, modification or redistribution of this Apple software constitutes acceptance of these terms. If you do not agree with these terms, please do not use, install, modify or redistribute this Apple software.

Thanks for this hint.
In addition to what you posted, I like that I can increase the number of services displayed directly in the contactual menu before going to the "Services" submenu. Worth the price (free) for this alone.

To uninstall Service Manager, delete the app, and search for "Service-Manager" (including hidden files). That will turn up a plist file and two (hidden) receipt files, which can then be deleted.

I found another free app "Services Item Menu Utility" on this page of the same website, which simply sets the maximum number of contextual menu services without a sub-menu. Actually, I extracted the AppleScript code from this app and use a modified version of that instead.

I had the same thought, but I think it may be because since Leopard it's
not really needed (although I like it). As he states on his Website:
"ENABLE-DISABLE SERVICES
Services can be turned off and on in the Keyboard Shortcuts tab of the Keyboard system preference pane (view)."